Fix workflow yet again

.github/workflows/build.yml

@@ -0,0 +1,19 @@
+name: "Build demo"
+on:
+  push:
+    branches:
+      - master
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: cachix/install-nix-action@v17
+        with:
+          nix_path: nixpkgs=channel:nixpkgs-unstable
+      - run: nix develop -c make build
+      - name: Deploy to GitHub Pages
+        uses: JamesIves/github-pages-deploy-action@v4.3.3
+        with:
+          branch: gh-pages
+          folder: public

.github/workflows/gh-pages.yml

@@ -1,23 +0,0 @@
-name: Build site
-
-on:
-  push:
-    branches:
-      - master
-
-jobs:
-  deploy:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: cachix/install-nix-action@v16
-      - name: Build website
-        run: |
-          chmod --recursive u+x ./bin/
-          nix develop -c make build
-      - name: Deploy
-        uses: peaceiris/actions-gh-pages@v3
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./public
-